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        <td class="header">&nbsp;<span style="font-weight: bold;"> Multi-Angle Pre-Processing</span><br>
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<p>Multi-Angle pre-processing takes a two C-band Quad Pol SLC
    products as input - a morning acquistion and an evening acquisition for
    the same date over the same area.</p>

<p>The order does not matter however, one product should be
    specified in the Read operator and the other in the Read(2) operator.</p>

<p class="MsoNormal" style="">The processing graph
    applies:</p>
<ul>
    <li>Radiometric calibration to Sigma0</li>
    <li>Mean 3x3 speckle filtering</li>
    <li>Terrain correction using the SRTM 3sec DEM and map
        projection to WGS84 Lat/Lng geographic coordinates
    </li>
</ul>
<p>The
    multi-angle soil moisture retrieval requires that the terrain
    correction operator output the incidence angle from the ellipsoid as a
    band.</p>

<p>The two terrain corrected results are then combined into a
    single product stack.</p>

<p>Pre-processing could also be applied from outside the Toolbox.
    In
    this case, the input product must adhere to the following input product
    conditions:</p>
<ol>
    <li>The input product must be calibrated to Sigma0</li>
    <li>All
        required source bands, namely, sigma0HH, sigma0VV
        and&nbsp;Incidence
        Angle&nbsp;must be present in a single input source product.
    </li>
    <li>The
        sigma0HH band name should contain "Sigma0_HH" or "HH" with "Sigma0_HH"
        taking precedence meaning that if a band whose name contains
        "Sigma0_HH" is found, other bands whose name contains "HH" will be
        ignored.
    </li>
    <li>The sigma0VV band name should contain "Sigma0_VV" or "VV"
        with "Sigma0_VV" taking precedence.
    </li>
    <li>If no unit is specified for the sigma0 bands or the unit is
        not decibel (dB), the sigma0 values will be converted to dB.
    </li>
    <li>The
        incidence angle band could be local incidence angle (LIA) or incidence
        angles from the ellipsoid. Incidence angles should be in degrees.
    </li>
    <li>The incidence angle band name should contain
        "incidenceAngle" or "LIA" with "incidenceAngle" taking precedence.
    </li>
    <li>It is assumed that the input product contains both AM and
        PM acquistions in a coregistered stack.
    </li>
    <li>There
        is a "master" band and the rest are "slave" bands. The name of the
        "master" band is assumed to contain "mst". The "slave" bands are
        assumed to be numbered such that their names contain "slvx" where x =
        1, 2, 3, ... , and so on. Assign the number 0 to the "master" band so
        that each band has a unique number. The bands are grouped into two
        images by their number order. The bands with lower numbers are grouped
        into one image while the bands with higher numbers are grouped into
        another image.
    </li>
</ol>
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